Read today's column: Target practice in Copenhagen in which Gene writes: "Climate-change skeptics are barking up the wrong smokestack. The shell game being played isn't with the science, it's with the solutions -- specifically, the carbon emissions targets that enlightened world leaders are pledging to meet. That's where the numbers don't add up."

Eugene Robinson: Hi, everybody. We have the Afghanistan speech tonight, the climate change conference in Copenhagen next week, and the health care debate (apparently) for the rest of our lives. Let's get started.

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Atlanta: I'm far from an expert on climate change - but I am getting the feeling that we are over-reacting here. The complexity of the world atmosphere is obvious, and at this point I just don't by the alarm. Look here in Atlanta - 3 years ago we were scrambling under an historic drought that threatened our drinking supply and today we sit with a flush Lake Lanier and flooding rains that destroy homes. I don't buy that this is somehow a result of overall climate change, and I'm not willing to extend national resources to combat something that is still so unknown. We changed our habits in Atlanta to adjust to the concerns and these changes were relatively painless and individual (use less water, buy more efficient water-consuming appliances, recycle rainwater) - isn't the proper course one that empowers the people to individually adjust to changes rather than impose government-wide emissions caps that, frankly, don't indicate much change (the earth has been cooler than anytime in the last 100 years in the past 12-14 months and surprise: two years of relative hurricane-free summers! Science doesn't match facts today...

Eugene Robinson: Well, it would be nice to ignore the climate change issue. It really would. But you do have to take a somewhat longer view than just the last year or two, and even if we confine ourselves to the most basic, directly observable facts, it's hard to conclude there's not a problem. We know that the past decade was the hottest since accurate records have been kept, and that it came after decades of warming. We know from ice cores that there's more carbon dioxide in the atmosphere than at any time in the last 800,000 years. We know CO2 is a greenhouse gas, and we know that humans have been spewing extraordinary amounts of the stuff into the air. Even if you don't go beyond that, you've got a problem.

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I've been a climate skeptic...: ...and always will be.

Here's why: global warming is supposedly caused by CO2 spewed by automobiles, factories, and even cows which cause a kind of greenhouse effect which raises temperatures.

Yet with that logic, nobody has been able to explain to me why there have been many global warmings and global coolings throughout history, way before the industrial revolution spewed its toxic stuff into the atmosphere.

Eugene Robinson: There are plenty of climatologists who can give you the best theories on natural cooling/warming cycles, including the extreme cycles that produced successive Ice Ages. They think it has to do with the Earth's orbit. What I can't get past is that even in warm cycles in the past, there has never been such a high concentration of CO2 in the atmosphere -- at least not in the last 8000 centuries.

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Baltimore: Mr. Robinson:

Given what we have learned in the past fortnight about the CRU emails, how was it even possible for you to write the independent clause "(t)he shell game being played isn't with the science"?

Eugene Robinson: I've looked pretty deeply into those CRU e-mails. And believe me, I'm not a climate change zealot -- I'd love it if someone discovered this was all a big misunderstanding. But I really don't think it is. I've read papers by the leading skeptics as well as those by the leading warming theorists, and I just don't believe that the e-mails show that climate science is rigged. They do lift the curtain on Scientists Behaving Badly -- professional jealousy, protection of turf, etc. -- but there's a lot more climate science out there and the CRU scandal doesn't negate it.

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Cumberland, Md.: Two thoughts on climate change--

1. If climate change is "man-made" why is there no discussion about population control? Fewer people means less impact on the environment.

2. Why is the WAPO and people like you ignoring the "climategate" scandal which personally I think is pretty big and being ignored by those who "support" climate change without questioning some of the obvious cooked up facts via the E-MAIL posted on web.

Eugene Robinson: Come on, my column last Friday was on the CRU e-mails. I don't know how many of them you've actually read, but I've read a bunch. And I've waded through some pretty dense papers to figure out what the e-mails were talking about.

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San Francisco: Eugene,

With all the inability to agree on GHG caps, and the uncertainty as to what those caps would actually produce, climate-wise, wouldn't we be better off spending about half the money on clean water, mosquito nets, AIDS and other medicines, relocating at-rick populations, etc. for the world's poor? These programs are pretty concrete as to cost vs. benefit and would give us some confidence that we saved some lives. Whereas with cutting carbon, we could spend all that money and still have disastrous climate change, or not have it but have no idea if our actions were responsible for the aversion or natural processes.

Eugene Robinson: Actually, I'm almost with you.

I disagree in the sense that I do think it makes sense to cut carbon usage. If we stay on the current trajectory, with China, India, Brazil and other nations developing carbon-based industrial economies, I think we can do real damage to ourselves and to the world we leave our grandchildren.

However, you make a good point. Poor nations are going to suffer most from climate change, since they're less equipped to adapt. But people in the developing world have much more pressing needs. If I had only ten dollars to try to help the people in a Congolese village, I'd use it to buy mosquito nets or water filters instead of some sort of solar oven that would cut their contribution to climate change.

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Brevard, N.C.: The question of CO2 is irrelevant. CO2 represents less than 1% of earth's atmosphere. Water vapor is the largest contributor to greenhouse gases, but can't be regulated by U.N., U.S. or global government. CO2 levels follow temperature rise and fall, by centuries, not the inverse. Until the tens of thousands of scientists/skeptics who disagree with the "consensus," and 3,000 climate scientists who submitted data and signed Senator Inhoffe's Minority Report to Congress on climate change are given exposure in MSM and columns, such as yours, this entire discussion is a fraud.

Eugene Robinson: The most respected, or at least credentialed, skeptics -- such as Prof. Richard Lindzer of MIT -- don't deny that carbon dioxide is a greenhouse gas. They do question how much it might have contributed to observed warming. CO2 levels have indeed lagged during episodes of natural warming, as in interglacial periods -- often they've lagged the onset of warming by hundreds of years. But this doesn't look like a natural episode. That's the point -- these levels of CO2 are unprecedented, at least in hundreds of thousands of years.

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Skepticville, USA: "What I can't get past is that even in warm cycles in the past, there has never been such a high concentration of CO2 in the atmosphere"

And yet, for the past 10 years the earth has been cooling. And these climate models that we're basing all the horrific consequences on can't account for it. Oh, and they won't let us see the data they're putting into these models. That's what I can't get past when they talk about throwing literally trillions of dollars at the "problem"

Eugene Robinson: It's not true that "for the past 10 years the earth has been cooling." It is true that 2008 was not as warm as 1998, but it's also true that the past decade was on average the warmest on record -- followed by the previous decade, followed by the previous one, etc. If the next ten years are cooler than the past ten, and then the following ten years are cooler still, I'll think that maybe you're onto something.

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Silver Spring, Md.: What to do about "Climate Change"?

IMHO, if the government does nothing, we'll all be driving electric cars in 20 years. Most of the world will be driving them in 40 years. Similar changes should be expected in meeting other energy needs.

We can take drastic steps to speed this change up, by maybe 10-20 years. But what is the difference in the global temperature say in 100 years? Is that difference worth the expense? Would it be better to spend that money on "adapting" to a higher global temperature?

Instead, we're told that only our "leaders" are capable enough to understand how we should proceed to reduce global temperatures and "control climate change".

I remain skeptical that "big brother" has the right answer.

Eugene Robinson: When we plug in those cars to charge them up, where's that electricity coming from? How's it going to be generated? Just asking.

You raise a good point, though, in that if the climate models are right (okay, and I know that some of you believe they're not, but humor me), we'll have continued warming for a long time even if we stop emitting carbon tomorrow. That's because it takes time for carbon dioxide to drain out of the atmosphere. So we're going to have to do some adaptation no matter what.

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Great Falls Va.: Dear Mr. Robinson, Instead of dismissing skeptics as a reporter why don't you investigate their claims? I know several University Professors who once believed in global warming and today they don't. A graduate student friend at Princeton's physics department recently told me the whole department doesn't believe in global warming anymore. Yes there are a lot of people who believe but that should not be the question - the question should be what does the science say. Opinions or belief means little if the science is flawed and I believe it's flawed. Now there's a story!

First, there's the argument that the earth has always had cycles of cooling and warming, so the planet will survive this. OK, sure, I agree that the planet will go on. But whether the currently existing species will continue -- including US, and the particular civilization that we have built -- is not the same question!

Second, they argue that we can't be sure that humans are causing/exacerbating the warming trend, so we don't know enough to justify making major changes and putting significant expense into reducing our impact. But, of course, if we guess wrong, and decide to do little or nothing, the consequences -- and costs, financial and otherwise -- of being wrong are going to be enormous.

In any event, I believe we will get to see those consequences play out, because I'm convinced we won't do anything truly significant until it's far too late to matter. And I'm not going to get much satisfaction out of saying "we told you so."

Eugene Robinson: Nor will I. The thing that drives me a little nuts is the idea that the fact that there have been natural heating-cooling cycles in the past somehow means that an unnatural, human-induced cycle is impossible. Why would that be true? And why would human-induced warming be expected to look just like natural warming?

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Herndon, Va.: In my view, climate skeptics are motivated by not wanting to take any action that would cost businesses and consumers in implementing alternative energy sources, etc. But what do climate change skeptics see as motivation on the part of scientists claiming global warming? Anti-business bias, wanting to pay more for energy?

Eugene Robinson: I guess they think the motivation is anti-business, but I'm not sure. Maybe they think the scientists are motivated by wanting to get tenure or win research grants, and believe that they can't advance their careers by taking the "wrong" position. And there's that old line about academic disputes being so fierce because the stakes are so low.

But of course the stakes are sky-high in this case. Look at it this way: Who wants to go down in history as one of the idiots who got it wrong on climate change? Most scientists really do want to get it right.

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Cumberland, Md.: How about population control and the result of unchecked population growth on climate change? Why did you ignore that question?

Eugene Robinson: I'm not big on population control. I've always thought of that as real Big Brother stuff. Fertility rates go down when women's education increases. We should build health clinics and schools, not scold people about having children.

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Burke, Va.: I'm a scientist who does believe that human activity does have some affect on global climate. However, as it has done for 4+ BILLION years, the Earth will compensate in an attempt to reach equilibrium, and it is not the "fragile ecosystem" climatologists want you to think it is. The Earth was completely covered in ice and snow at least FOUR TIMES, and was many degrees warmer than it is today a little more than 500,000 years ago (less than "day" in the lifespan of the Earth).

That's the real problem I have with all of the global warming theorists. They sound the panic alarms based on miniscule datasets. We only have global climate data from the past 100 or so years, and of those data, only about 25 or so of the most recent years are solidly accurate collected with precision instruments. So these so-called "scientists" have 25 years of defensible data on a planet with billions of years under its belt, yet they try to draw conclusions based on that infinitely small set of data. That's where the media and the general public need to wake up and understand that all of these Chicken Littles are not doing the world any good. They say the Earth was cooler in 1895 when they got those data from local newspapers printing the temperature calculated by crude mercury thermometers on some farmer's porch.

Do I think that humans can work to reduce our footprint on our home planet, sure, but should we bring progress to a grinding halt and revert back to stone-age technologies, absolutely not.

Eugene Robinson: Well, but who's talking about bringing progress to a grinding halt or reverting to Stone Age technologies? Is that really what we're talking about? If you believe that human activity is contributing and that we should reduce our footprint, they're never going to let you into the Skeptics Club.

My time is up for today, folks. Thanks for a lively hour. See you again next week.

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